Koko Collection

Young Koko has just moved with his parents from his idyllic countryside home to a big city. There, with the help of his new friends and a neighbour he investigates the mysterious case of a dead old man who used to live in the flat he has just moved into.

Mirko's secret becomes an adventure of Koko, Tomo and Marijana.

It seems that football is still the most important thing in Koko's life. Zlatko is still spending every second reading books and scolding Koko for being immature. To prove him wrong, Koko tells him that he is in love with a mysterious girl. His love for her is not making him happy.

Koko and his friends are spending summer vacation on the shores of a lake near the idyllic Green Hill, hanging out and playing. The magical countryside is disturbed by unusual events which alarm the children as well as the locals: under cover of night, burglars break into one house after another, stealing anything valuable they can find.